How do you script batch changes to bone constraints
I'd go about it this way.  I use context = bpy.context on test scripts, that can later be pasted into Operator or Panel code.  Work from the context object, rather than using a name like "Armature.001" (guilty myself on many occasions)

I use list comprehension out of preference. 

import bpy
context = bpy.context
# the rig object
rig = context.object

# all copy location constraints on all pose bones
constraints = [c for pb in rig.pose.bones 
                 for c in pb.constraints
                 if c.type == 'COPY_LOCATION'
               # and "XY" in c.name
              ]

# set the desired properties
for c in constraints:
    c.use_y = True

# similarly for Transformation
# type from mousing over add constraint in UI
constraints = [c for pb in rig.pose.bones 
                 for c in pb.constraints
                 if c.type == 'TRANSFORM'
              ]

for tc in constraints:
    tc.to_max_y = 0.02 # given 1 blender unit is 1m


# all constraints from preselected pose bones
constraints = [c for pb in context.selected_pose_bones 
                 for c in pb.constraints
              ]